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    P charts based on binomial distribution - Statistical Process Control

    Hello all, I have a question related to the use of p-chart in a process where there are defect rates measured. The control limits for this type of chart is calculated with +/- 3 sigmas around the mean (with mean = np and sd = sqrt(n*(1-p)*p)) As it is using i +/- 3 sigmas it assumes that we...
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    Include supplementary individuals PCA with PROC PRINCOMP

    Hello, I am using PCA with PROC PRINCOMP to perform multivariate statistical process control and would like to build a PCA only on a certain set of individuals and let the others as supplementary. Anyone knows how to do it? I know this functionality exists with other software such as R...
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    Interpret Linear Discriminant Analysis and visualization

    Hello, I performed a LDA in R but I'm a bit concerned about how I could present my results. I didn't do any scaling before the data analysis, is it recommended to do so? When I do the LDA, I got the following coefficients: Coefficients of linear discriminants: LD1 CHP -8.7908674 CD...
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    Compute prediction intervals in Random Forest Regression

    Hello, I am trying to use Random Forest Regression to better predict the output of a manufacturing process. Until now, I was using PLS regression to do so but it turned out that Random Forest Regression gave better results (lower RMSE on the test dataset). My main concern is that I am not able...
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    Hello statisticians and data enthusiasts!

    Hello everyone, I just joined the forum and posted my first message some minutes ago. I am statistician working in a pharmaceutical industrial sites and thus apply statistics to industrial field. I hope we could share some of the statistics that are used in Industry such as Statistical Process...
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    Design of experiments across the time

    Hi all, I am trying to model a continous variable across the time with several timepoints (0,3,6,9 and 12 months) and 2 predictors. One is continuous (5 and 10) and the other is categorical (A, B and C) and for each of the combinaison I have 30 replicates. The relation between Y and the...